The minimum wall thickness, required for strength, buckling and fatigue due to vortices can be determined with a computer program where with alterations the minimum plate thickness can be derived. Step by step the resonance frequencies and the wind load are determined for chimneys with or without guys. The need for a damper system will be indicated. This depends on the confining load: extreme wind pressure or fatigue due to vortex shedding. A choice between a damper or helical strakes can be made. The calculation of the stresses due to vortex shedding is based on the method of Vickery and the CICIND Model Code. The Miner sum will be calculated to see the possibility of collapse by fatigue. If a damper system is necessary the effect on the damping of the chimney can be introduced, depending on the effect of the damper. Corrosion thickness can be introduced or changed at every height. The dimensions of flanges, base plate and connection bolts are given. If required the minimum dimension of round or square foundation blocks of concrete including the reinforcement can be calculated.

Dynamics in civil engineering

• Life time estimation of existing structures
• Reduction of undesirable movements like machine foundations
• Calculation of :
  • earthquake load
  • machine foundation
  • pressure vessels
  • shell structures
  • vibration insulation
  • wind load

Machine foundations

Many years of experience and tests have made it possible to write a report on stiffness and damping of machine foundations. The influence of the stiffness and damping of the soil has been determined and the effect on simple foundation blocks and on piles have been measured and compared with theoretical expressions. The latter makes it possible to make accurate calculations of the behavior of foundations on the loading by machines.
Many designs have been checked and the movements of the buildings around have been measured and compared with the calculation results. The design method has proven to be close to reality. The movements of the foundations, the machines and the surroundings are close to all calculated values.
The method is an improvement compared with existing calculations.